49 
NOTE ON COLOURATION IN TICKS. 
By GEORGE H. F. NUTTALL, F.R.S. 
{From tlie Quick Laboratory, University of Cambridge.) 
(With Plate VII.) 
The ornamentation so characteristic in Amblyomma, Aponomma, 
Dermacentor, and occasionally met with in species of Rhipicephalus and 
Hyalomma, is of use to the systematist in the differentiation of species. 
In many descriptions of ornate Ixodidae the colours are referred to as 
“ metallic ” owing to the sheen they possess when the ticks are preserved 
in alcohol. 
Whereas many authors no doubt describe the colours as they are 
seen in specimens preserved in alcohol, others appear to describe them 
from dried specimens. The object of this note is merely to point out 
that authors should state in their descriptions whether the ornamentation 
is described from specimens pi’eserved in alcohol or simply dried, and 
to enter a plea with workers in the field that they should, wherever 
possible, note the colours of living ticks. 
The accompanying Plate (VII) will serve to illustrate my remarks. It 
is the very accurate work of Mr Edwin Wilson, based on camera-lucida 
drawings of my own, the colouration of the scutum being an exact 
reproduction of what is seen by daylight both in living and in well- 
preserved dried specimens of Amblyomma variegatum {if and $) and 
A. splendidum {if). Thanks to the kindness of a correspondent in 
the Lower Congo, I have recently come into the possession of living 
specimens (N. 1650 and 1650a) of the foregoing species of ticks, the 
first, I believe, that have arrived in a living condition in Europe. In 
view of the beautiful ornamentation shown by the living ticks I could 
not resist the temptation to illustrate them. 
It will be seen that the chief markings are retained in dried 
specimens and a comparison with ticks preserved in alcohol shows that 
Parasitology vi 4 
